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<a name="1" href="#1">1</a>   <em class="jxr_comment">/*</em>
<a name="2" href="#2">2</a>   <em class="jxr_comment"> * Licensed to the Apache Software Foundation (ASF) under one or more</em>
<a name="3" href="#3">3</a>   <em class="jxr_comment"> * contributor license agreements.  See the NOTICE file distributed with</em>
<a name="4" href="#4">4</a>   <em class="jxr_comment"> * this work for additional information regarding copyright ownership.</em>
<a name="5" href="#5">5</a>   <em class="jxr_comment"> * The ASF licenses this file to You under the Apache License, Version 2.0</em>
<a name="6" href="#6">6</a>   <em class="jxr_comment"> * (the "License"); you may not use this file except in compliance with</em>
<a name="7" href="#7">7</a>   <em class="jxr_comment"> * the License.  You may obtain a copy of the License at</em>
<a name="8" href="#8">8</a>   <em class="jxr_comment"> * </em>
<a name="9" href="#9">9</a>   <em class="jxr_comment"> *      <a href="http://www.apache.org/licenses/LICENSE-2.0" target="alexandria_uri">http://www.apache.org/licenses/LICENSE-2.0</a></em>
<a name="10" href="#10">10</a>  <em class="jxr_comment"> * </em>
<a name="11" href="#11">11</a>  <em class="jxr_comment"> * Unless required by applicable law or agreed to in writing, software</em>
<a name="12" href="#12">12</a>  <em class="jxr_comment"> * distributed under the License is distributed on an "AS IS" BASIS,</em>
<a name="13" href="#13">13</a>  <em class="jxr_comment"> * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.</em>
<a name="14" href="#14">14</a>  <em class="jxr_comment"> * See the License for the specific language governing permissions and</em>
<a name="15" href="#15">15</a>  <em class="jxr_comment"> * limitations under the License.</em>
<a name="16" href="#16">16</a>  <em class="jxr_comment"> */</em> 
<a name="17" href="#17">17</a>  
<a name="18" href="#18">18</a>  <strong class="jxr_keyword">package</strong> org.apache.commons.logging;
<a name="19" href="#19">19</a>  
<a name="20" href="#20">20</a>  <strong class="jxr_keyword">import</strong> java.io.File;
<a name="21" href="#21">21</a>  <strong class="jxr_keyword">import</strong> java.io.IOException;
<a name="22" href="#22">22</a>  <strong class="jxr_keyword">import</strong> java.io.InputStream;
<a name="23" href="#23">23</a>  <strong class="jxr_keyword">import</strong> java.net.URL;
<a name="24" href="#24">24</a>  <strong class="jxr_keyword">import</strong> java.net.URLClassLoader;
<a name="25" href="#25">25</a>  <strong class="jxr_keyword">import</strong> java.util.ArrayList;
<a name="26" href="#26">26</a>  <strong class="jxr_keyword">import</strong> java.util.Collections;
<a name="27" href="#27">27</a>  <strong class="jxr_keyword">import</strong> java.util.Enumeration;
<a name="28" href="#28">28</a>  <strong class="jxr_keyword">import</strong> java.util.HashMap;
<a name="29" href="#29">29</a>  <strong class="jxr_keyword">import</strong> java.util.Iterator;
<a name="30" href="#30">30</a>  <strong class="jxr_keyword">import</strong> java.util.Map;
<a name="31" href="#31">31</a>  
<a name="32" href="#32">32</a>  <em class="jxr_javadoccomment">/**</em>
<a name="33" href="#33">33</a>  <em class="jxr_javadoccomment"> * A ClassLoader which sees only specified classes, and which can be</em>
<a name="34" href="#34">34</a>  <em class="jxr_javadoccomment"> * set to do parent-first or child-first path lookup.</em>
<a name="35" href="#35">35</a>  <em class="jxr_javadoccomment"> * &lt;p&gt;</em>
<a name="36" href="#36">36</a>  <em class="jxr_javadoccomment"> * Note that this classloader is not "industrial strength"; users</em>
<a name="37" href="#37">37</a>  <em class="jxr_javadoccomment"> * looking for such a class may wish to look at the Tomcat sourcecode</em>
<a name="38" href="#38">38</a>  <em class="jxr_javadoccomment"> * instead. In particular, this class may not be threadsafe.</em>
<a name="39" href="#39">39</a>  <em class="jxr_javadoccomment"> * &lt;p&gt;</em>
<a name="40" href="#40">40</a>  <em class="jxr_javadoccomment"> * Note that the ClassLoader.getResources method isn't overloaded here.</em>
<a name="41" href="#41">41</a>  <em class="jxr_javadoccomment"> * It would be nice to ensure that when child-first lookup is set the</em>
<a name="42" href="#42">42</a>  <em class="jxr_javadoccomment"> * resources from the child are returned earlier in the list than the</em>
<a name="43" href="#43">43</a>  <em class="jxr_javadoccomment"> * resources from the parent. However overriding this method isn't possible</em>
<a name="44" href="#44">44</a>  <em class="jxr_javadoccomment"> * as the java 1.4 version of ClassLoader declares this method final</em>
<a name="45" href="#45">45</a>  <em class="jxr_javadoccomment"> * (though the java 1.5 version has removed the final qualifier). As the</em>
<a name="46" href="#46">46</a>  <em class="jxr_javadoccomment"> * ClassLoader javadoc doesn't specify the order in which resources</em>
<a name="47" href="#47">47</a>  <em class="jxr_javadoccomment"> * are returned, it's valid to return the resources in any order (just</em>
<a name="48" href="#48">48</a>  <em class="jxr_javadoccomment"> * untidy) so the inherited implementation is technically ok.</em>
<a name="49" href="#49">49</a>  <em class="jxr_javadoccomment"> */</em>
<a name="50" href="#50">50</a>  
<a name="51" href="#51">51</a>  <strong class="jxr_keyword">public</strong> <strong class="jxr_keyword">class</strong> <a href="../../../../org/apache/commons/logging/PathableClassLoader.html">PathableClassLoader</a> <strong class="jxr_keyword">extends</strong> URLClassLoader {
<a name="52" href="#52">52</a>      
<a name="53" href="#53">53</a>      <strong class="jxr_keyword">private</strong> <strong class="jxr_keyword">static</strong> <strong class="jxr_keyword">final</strong> URL[] NO_URLS = <strong class="jxr_keyword">new</strong> URL[0];
<a name="54" href="#54">54</a>      
<a name="55" href="#55">55</a>      <em class="jxr_javadoccomment">/**</em>
<a name="56" href="#56">56</a>  <em class="jxr_javadoccomment">     * A map of package-prefix to ClassLoader. Any class which is in</em>
<a name="57" href="#57">57</a>  <em class="jxr_javadoccomment">     * this map is looked up via the specified classloader instead of</em>
<a name="58" href="#58">58</a>  <em class="jxr_javadoccomment">     * the classpath associated with this classloader or its parents.</em>
<a name="59" href="#59">59</a>  <em class="jxr_javadoccomment">     * &lt;p&gt;</em>
<a name="60" href="#60">60</a>  <em class="jxr_javadoccomment">     * This is necessary in order for the rest of the world to communicate</em>
<a name="61" href="#61">61</a>  <em class="jxr_javadoccomment">     * with classes loaded via a custom classloader. As an example, junit</em>
<a name="62" href="#62">62</a>  <em class="jxr_javadoccomment">     * testcases which are loaded via a custom classloader needs to see</em>
<a name="63" href="#63">63</a>  <em class="jxr_javadoccomment">     * the same junit classes as the code invoking the testcase, otherwise</em>
<a name="64" href="#64">64</a>  <em class="jxr_javadoccomment">     * they can't pass result objects back. </em>
<a name="65" href="#65">65</a>  <em class="jxr_javadoccomment">     * &lt;p&gt;</em>
<a name="66" href="#66">66</a>  <em class="jxr_javadoccomment">     * Normally, only a classloader created with a null parent needs to</em>
<a name="67" href="#67">67</a>  <em class="jxr_javadoccomment">     * have any lookasides defined.</em>
<a name="68" href="#68">68</a>  <em class="jxr_javadoccomment">     */</em>
<a name="69" href="#69">69</a>      <strong class="jxr_keyword">private</strong> HashMap lookasides = <strong class="jxr_keyword">null</strong>;
<a name="70" href="#70">70</a>  
<a name="71" href="#71">71</a>      <em class="jxr_javadoccomment">/**</em>
<a name="72" href="#72">72</a>  <em class="jxr_javadoccomment">     * See setParentFirst.</em>
<a name="73" href="#73">73</a>  <em class="jxr_javadoccomment">     */</em>
<a name="74" href="#74">74</a>      <strong class="jxr_keyword">private</strong> <strong class="jxr_keyword">boolean</strong> parentFirst = <strong class="jxr_keyword">true</strong>;
<a name="75" href="#75">75</a>  
<a name="76" href="#76">76</a>      <em class="jxr_javadoccomment">/**</em>
<a name="77" href="#77">77</a>  <em class="jxr_javadoccomment">     * Constructor.</em>
<a name="78" href="#78">78</a>  <em class="jxr_javadoccomment">     * &lt;p&gt;</em>
<a name="79" href="#79">79</a>  <em class="jxr_javadoccomment">     * Often, null is passed as the parent, ie the parent of the new</em>
<a name="80" href="#80">80</a>  <em class="jxr_javadoccomment">     * instance is the bootloader. This ensures that the classpath is</em>
<a name="81" href="#81">81</a>  <em class="jxr_javadoccomment">     * totally clean; nothing but the standard java library will be</em>
<a name="82" href="#82">82</a>  <em class="jxr_javadoccomment">     * present.</em>
<a name="83" href="#83">83</a>  <em class="jxr_javadoccomment">     * &lt;p&gt;</em>
<a name="84" href="#84">84</a>  <em class="jxr_javadoccomment">     * When using a null parent classloader with a junit testcase, it *is*</em>
<a name="85" href="#85">85</a>  <em class="jxr_javadoccomment">     * necessary for the junit library to also be visible. In this case, it</em>
<a name="86" href="#86">86</a>  <em class="jxr_javadoccomment">     * is recommended that the following code be used:</em>
<a name="87" href="#87">87</a>  <em class="jxr_javadoccomment">     * &lt;pre&gt;</em>
<a name="88" href="#88">88</a>  <em class="jxr_javadoccomment">     * pathableLoader.useExplicitLoader(</em>
<a name="89" href="#89">89</a>  <em class="jxr_javadoccomment">     *   "junit.",</em>
<a name="90" href="#90">90</a>  <em class="jxr_javadoccomment">     *   junit.framework.Test.class.getClassLoader());</em>
<a name="91" href="#91">91</a>  <em class="jxr_javadoccomment">     * &lt;/pre&gt;</em>
<a name="92" href="#92">92</a>  <em class="jxr_javadoccomment">     * Note that this works regardless of whether junit is on the system</em>
<a name="93" href="#93">93</a>  <em class="jxr_javadoccomment">     * classpath, or whether it has been loaded by some test framework that</em>
<a name="94" href="#94">94</a>  <em class="jxr_javadoccomment">     * creates its own classloader to run unit tests in (eg maven2's</em>
<a name="95" href="#95">95</a>  <em class="jxr_javadoccomment">     * Surefire plugin).</em>
<a name="96" href="#96">96</a>  <em class="jxr_javadoccomment">     */</em>
<a name="97" href="#97">97</a>      <strong class="jxr_keyword">public</strong> <a href="../../../../org/apache/commons/logging/PathableClassLoader.html">PathableClassLoader</a>(ClassLoader parent) {
<a name="98" href="#98">98</a>          <strong class="jxr_keyword">super</strong>(NO_URLS, parent);
<a name="99" href="#99">99</a>      }
<a name="100" href="#100">100</a>     
<a name="101" href="#101">101</a>     <em class="jxr_javadoccomment">/**</em>
<a name="102" href="#102">102</a> <em class="jxr_javadoccomment">     * Allow caller to explicitly add paths. Generally this not a good idea;</em>
<a name="103" href="#103">103</a> <em class="jxr_javadoccomment">     * use addLogicalLib instead, then define the location for that logical</em>
<a name="104" href="#104">104</a> <em class="jxr_javadoccomment">     * library in the build.xml file.</em>
<a name="105" href="#105">105</a> <em class="jxr_javadoccomment">     */</em>
<a name="106" href="#106">106</a>     <strong class="jxr_keyword">public</strong> <strong class="jxr_keyword">void</strong> addURL(URL url) {
<a name="107" href="#107">107</a>         <strong class="jxr_keyword">super</strong>.addURL(url);
<a name="108" href="#108">108</a>     }
<a name="109" href="#109">109</a> 
<a name="110" href="#110">110</a>     <em class="jxr_javadoccomment">/**</em>
<a name="111" href="#111">111</a> <em class="jxr_javadoccomment">     * Specify whether this classloader should ask the parent classloader</em>
<a name="112" href="#112">112</a> <em class="jxr_javadoccomment">     * to resolve a class first, before trying to resolve it via its own</em>
<a name="113" href="#113">113</a> <em class="jxr_javadoccomment">     * classpath.</em>
<a name="114" href="#114">114</a> <em class="jxr_javadoccomment">     * &lt;p&gt; </em>
<a name="115" href="#115">115</a> <em class="jxr_javadoccomment">     * Checking with the parent first is the normal approach for java, but</em>
<a name="116" href="#116">116</a> <em class="jxr_javadoccomment">     * components within containers such as servlet engines can use </em>
<a name="117" href="#117">117</a> <em class="jxr_javadoccomment">     * child-first lookup instead, to allow the components to override libs</em>
<a name="118" href="#118">118</a> <em class="jxr_javadoccomment">     * which are visible in shared classloaders provided by the container.</em>
<a name="119" href="#119">119</a> <em class="jxr_javadoccomment">     * &lt;p&gt;</em>
<a name="120" href="#120">120</a> <em class="jxr_javadoccomment">     * Note that the method getResources always behaves as if parentFirst=true,</em>
<a name="121" href="#121">121</a> <em class="jxr_javadoccomment">     * because of limitations in java 1.4; see the javadoc for method</em>
<a name="122" href="#122">122</a> <em class="jxr_javadoccomment">     * getResourcesInOrder for details.</em>
<a name="123" href="#123">123</a> <em class="jxr_javadoccomment">     * &lt;p&gt;</em>
<a name="124" href="#124">124</a> <em class="jxr_javadoccomment">     * This value defaults to true.</em>
<a name="125" href="#125">125</a> <em class="jxr_javadoccomment">     */</em>
<a name="126" href="#126">126</a>     <strong class="jxr_keyword">public</strong> <strong class="jxr_keyword">void</strong> setParentFirst(<strong class="jxr_keyword">boolean</strong> state) {
<a name="127" href="#127">127</a>         parentFirst = state;
<a name="128" href="#128">128</a>     }
<a name="129" href="#129">129</a> 
<a name="130" href="#130">130</a>     <em class="jxr_javadoccomment">/**</em>
<a name="131" href="#131">131</a> <em class="jxr_javadoccomment">     * For classes with the specified prefix, get them from the system</em>
<a name="132" href="#132">132</a> <em class="jxr_javadoccomment">     * classpath &lt;i&gt;which is active at the point this method is called&lt;/i&gt;.</em>
<a name="133" href="#133">133</a> <em class="jxr_javadoccomment">     * &lt;p&gt;</em>
<a name="134" href="#134">134</a> <em class="jxr_javadoccomment">     * This method is just a shortcut for</em>
<a name="135" href="#135">135</a> <em class="jxr_javadoccomment">     * &lt;pre&gt;</em>
<a name="136" href="#136">136</a> <em class="jxr_javadoccomment">     * useExplicitLoader(prefix, ClassLoader.getSystemClassLoader());</em>
<a name="137" href="#137">137</a> <em class="jxr_javadoccomment">     * &lt;/pre&gt;</em>
<a name="138" href="#138">138</a> <em class="jxr_javadoccomment">     * &lt;p&gt;</em>
<a name="139" href="#139">139</a> <em class="jxr_javadoccomment">     * Of course, this assumes that the classes of interest are already</em>
<a name="140" href="#140">140</a> <em class="jxr_javadoccomment">     * in the classpath of the system classloader.</em>
<a name="141" href="#141">141</a> <em class="jxr_javadoccomment">     */</em>
<a name="142" href="#142">142</a>     <strong class="jxr_keyword">public</strong> <strong class="jxr_keyword">void</strong> useSystemLoader(String prefix) {
<a name="143" href="#143">143</a>         useExplicitLoader(prefix, ClassLoader.getSystemClassLoader());
<a name="144" href="#144">144</a>         
<a name="145" href="#145">145</a>     }
<a name="146" href="#146">146</a> 
<a name="147" href="#147">147</a>     <em class="jxr_javadoccomment">/**</em>
<a name="148" href="#148">148</a> <em class="jxr_javadoccomment">     * Specify a classloader to use for specific java packages.</em>
<a name="149" href="#149">149</a> <em class="jxr_javadoccomment">     * &lt;p&gt;</em>
<a name="150" href="#150">150</a> <em class="jxr_javadoccomment">     * The specified classloader is normally a loader that is NOT</em>
<a name="151" href="#151">151</a> <em class="jxr_javadoccomment">     * an ancestor of this classloader. In particular, this loader</em>
<a name="152" href="#152">152</a> <em class="jxr_javadoccomment">     * may have the bootloader as its parent, but be configured to </em>
<a name="153" href="#153">153</a> <em class="jxr_javadoccomment">     * see specific other classes (eg the junit library loaded</em>
<a name="154" href="#154">154</a> <em class="jxr_javadoccomment">     * via the system classloader).</em>
<a name="155" href="#155">155</a> <em class="jxr_javadoccomment">     * &lt;p&gt;</em>
<a name="156" href="#156">156</a> <em class="jxr_javadoccomment">     * The differences between using this method, and using</em>
<a name="157" href="#157">157</a> <em class="jxr_javadoccomment">     * addLogicalLib are:</em>
<a name="158" href="#158">158</a> <em class="jxr_javadoccomment">     * &lt;ul&gt;</em>
<a name="159" href="#159">159</a> <em class="jxr_javadoccomment">     * &lt;li&gt;If code calls getClassLoader on a class loaded via</em>
<a name="160" href="#160">160</a> <em class="jxr_javadoccomment">     * "lookaside", then traces up its inheritance chain, it</em>
<a name="161" href="#161">161</a> <em class="jxr_javadoccomment">     * will see the "real" classloaders. When the class is remapped</em>
<a name="162" href="#162">162</a> <em class="jxr_javadoccomment">     * into this classloader via addLogicalLib, the classloader</em>
<a name="163" href="#163">163</a> <em class="jxr_javadoccomment">     * chain seen is this object plus ancestors.</em>
<a name="164" href="#164">164</a> <em class="jxr_javadoccomment">     * &lt;li&gt;If two different jars contain classes in the same</em>
<a name="165" href="#165">165</a> <em class="jxr_javadoccomment">     * package, then it is not possible to load both jars into</em>
<a name="166" href="#166">166</a> <em class="jxr_javadoccomment">     * the same "lookaside" classloader (eg the system classloader)</em>
<a name="167" href="#167">167</a> <em class="jxr_javadoccomment">     * then map one of those subsets from here. Of course they could</em>
<a name="168" href="#168">168</a> <em class="jxr_javadoccomment">     * be loaded into two different "lookaside" classloaders and</em>
<a name="169" href="#169">169</a> <em class="jxr_javadoccomment">     * then a prefix used to map from here to one of those classloaders.</em>
<a name="170" href="#170">170</a> <em class="jxr_javadoccomment">     * &lt;/ul&gt;</em>
<a name="171" href="#171">171</a> <em class="jxr_javadoccomment">     */</em>
<a name="172" href="#172">172</a>     <strong class="jxr_keyword">public</strong> <strong class="jxr_keyword">void</strong> useExplicitLoader(String prefix, ClassLoader loader) {
<a name="173" href="#173">173</a>         <strong class="jxr_keyword">if</strong> (lookasides == <strong class="jxr_keyword">null</strong>) {
<a name="174" href="#174">174</a>             lookasides = <strong class="jxr_keyword">new</strong> HashMap();
<a name="175" href="#175">175</a>         }
<a name="176" href="#176">176</a>         lookasides.put(prefix, loader);
<a name="177" href="#177">177</a>     }
<a name="178" href="#178">178</a> 
<a name="179" href="#179">179</a>     <em class="jxr_javadoccomment">/**</em>
<a name="180" href="#180">180</a> <em class="jxr_javadoccomment">     * Specify a collection of logical libraries. See addLogicalLib.</em>
<a name="181" href="#181">181</a> <em class="jxr_javadoccomment">     */</em>
<a name="182" href="#182">182</a>     <strong class="jxr_keyword">public</strong> <strong class="jxr_keyword">void</strong> addLogicalLib(String[] logicalLibs) {
<a name="183" href="#183">183</a>         <strong class="jxr_keyword">for</strong>(<strong class="jxr_keyword">int</strong> i=0; i&lt;logicalLibs.length; ++i) {
<a name="184" href="#184">184</a>             addLogicalLib(logicalLibs[i]);
<a name="185" href="#185">185</a>         }
<a name="186" href="#186">186</a>     }
<a name="187" href="#187">187</a> 
<a name="188" href="#188">188</a>     <em class="jxr_javadoccomment">/**</em>
<a name="189" href="#189">189</a> <em class="jxr_javadoccomment">     * Specify a logical library to be included in the classpath used to</em>
<a name="190" href="#190">190</a> <em class="jxr_javadoccomment">     * locate classes. </em>
<a name="191" href="#191">191</a> <em class="jxr_javadoccomment">     * &lt;p&gt;</em>
<a name="192" href="#192">192</a> <em class="jxr_javadoccomment">     * The specified lib name is used as a key into the system properties;</em>
<a name="193" href="#193">193</a> <em class="jxr_javadoccomment">     * there is expected to be a system property defined with that name</em>
<a name="194" href="#194">194</a> <em class="jxr_javadoccomment">     * whose value is a url that indicates where that logical library can</em>
<a name="195" href="#195">195</a> <em class="jxr_javadoccomment">     * be found. Typically this is the name of a jar file, or a directory</em>
<a name="196" href="#196">196</a> <em class="jxr_javadoccomment">     * containing class files.</em>
<a name="197" href="#197">197</a> <em class="jxr_javadoccomment">     * &lt;p&gt;</em>
<a name="198" href="#198">198</a> <em class="jxr_javadoccomment">     * If there is no system property, but the classloader that loaded</em>
<a name="199" href="#199">199</a> <em class="jxr_javadoccomment">     * this class is a URLClassLoader then the set of URLs that the</em>
<a name="200" href="#200">200</a> <em class="jxr_javadoccomment">     * classloader uses for its classpath is scanned; any jar in the</em>
<a name="201" href="#201">201</a> <em class="jxr_javadoccomment">     * URL set whose name starts with the specified string is added to</em>
<a name="202" href="#202">202</a> <em class="jxr_javadoccomment">     * the classpath managed by this instance. </em>
<a name="203" href="#203">203</a> <em class="jxr_javadoccomment">     * &lt;p&gt;</em>
<a name="204" href="#204">204</a> <em class="jxr_javadoccomment">     * Using logical library names allows the calling code to specify its</em>
<a name="205" href="#205">205</a> <em class="jxr_javadoccomment">     * desired classpath without knowing the exact location of the necessary</em>
<a name="206" href="#206">206</a> <em class="jxr_javadoccomment">     * classes. </em>
<a name="207" href="#207">207</a> <em class="jxr_javadoccomment">     */</em>
<a name="208" href="#208">208</a>     <strong class="jxr_keyword">public</strong> <strong class="jxr_keyword">void</strong> addLogicalLib(String logicalLib) {
<a name="209" href="#209">209</a>         <em class="jxr_comment">// first, check the system properties</em>
<a name="210" href="#210">210</a>         String filename = System.getProperty(logicalLib);
<a name="211" href="#211">211</a>         <strong class="jxr_keyword">if</strong> (filename != <strong class="jxr_keyword">null</strong>) {
<a name="212" href="#212">212</a>             <strong class="jxr_keyword">try</strong> {
<a name="213" href="#213">213</a>                 URL libUrl = <strong class="jxr_keyword">new</strong> File(filename).toURL();
<a name="214" href="#214">214</a>                 addURL(libUrl);
<a name="215" href="#215">215</a>                 <strong class="jxr_keyword">return</strong>;
<a name="216" href="#216">216</a>             } <strong class="jxr_keyword">catch</strong>(java.net.MalformedURLException e) {
<a name="217" href="#217">217</a>                 <strong class="jxr_keyword">throw</strong> <strong class="jxr_keyword">new</strong> UnknownError(
<a name="218" href="#218">218</a>                     <span class="jxr_string">"Invalid file ["</span> + filename + <span class="jxr_string">"] for logical lib ["</span> + logicalLib + <span class="jxr_string">"]"</span>);
<a name="219" href="#219">219</a>             }
<a name="220" href="#220">220</a>         }
<a name="221" href="#221">221</a> 
<a name="222" href="#222">222</a>         <em class="jxr_comment">// now check the classpath for a similar-named lib</em>
<a name="223" href="#223">223</a>         URL libUrl = libFromClasspath(logicalLib);
<a name="224" href="#224">224</a>         <strong class="jxr_keyword">if</strong> (libUrl != <strong class="jxr_keyword">null</strong>) {
<a name="225" href="#225">225</a>             addURL(libUrl);
<a name="226" href="#226">226</a>             <strong class="jxr_keyword">return</strong>;
<a name="227" href="#227">227</a>         }
<a name="228" href="#228">228</a> 
<a name="229" href="#229">229</a>         <em class="jxr_comment">// lib not found</em>
<a name="230" href="#230">230</a>         <strong class="jxr_keyword">throw</strong> <strong class="jxr_keyword">new</strong> UnknownError(
<a name="231" href="#231">231</a>             <span class="jxr_string">"Logical lib ["</span> + logicalLib + <span class="jxr_string">"] is not defined"</span>
<a name="232" href="#232">232</a>             + <span class="jxr_string">" as a System property."</span>);
<a name="233" href="#233">233</a>     }
<a name="234" href="#234">234</a> 
<a name="235" href="#235">235</a>     <em class="jxr_javadoccomment">/**</em>
<a name="236" href="#236">236</a> <em class="jxr_javadoccomment">     * If the classloader that loaded this class has this logical lib in its</em>
<a name="237" href="#237">237</a> <em class="jxr_javadoccomment">     * path, then return the matching URL otherwise return null.</em>
<a name="238" href="#238">238</a> <em class="jxr_javadoccomment">     * &lt;p&gt;</em>
<a name="239" href="#239">239</a> <em class="jxr_javadoccomment">     * This only works when the classloader loading this class is an instance</em>
<a name="240" href="#240">240</a> <em class="jxr_javadoccomment">     * of URLClassLoader and thus has a getURLs method that returns the classpath</em>
<a name="241" href="#241">241</a> <em class="jxr_javadoccomment">     * it uses when loading classes. However in practice, the vast majority of the</em>
<a name="242" href="#242">242</a> <em class="jxr_javadoccomment">     * time this type is the classloader used.</em>
<a name="243" href="#243">243</a> <em class="jxr_javadoccomment">     * &lt;p&gt;</em>
<a name="244" href="#244">244</a> <em class="jxr_javadoccomment">     * The classpath of the classloader for this instance is scanned, and any</em>
<a name="245" href="#245">245</a> <em class="jxr_javadoccomment">     * jarfile in the path whose name starts with the logicalLib string is</em>
<a name="246" href="#246">246</a> <em class="jxr_javadoccomment">     * considered a match. For example, passing "foo" will match a url</em>
<a name="247" href="#247">247</a> <em class="jxr_javadoccomment">     * of &lt;code&gt;file:///some/where/foo-2.7.jar&lt;/code&gt;.</em>
<a name="248" href="#248">248</a> <em class="jxr_javadoccomment">     * &lt;p&gt;</em>
<a name="249" href="#249">249</a> <em class="jxr_javadoccomment">     * When multiple classpath entries match the specified logicalLib string,</em>
<a name="250" href="#250">250</a> <em class="jxr_javadoccomment">     * the one with the shortest filename component is returned. This means that</em>
<a name="251" href="#251">251</a> <em class="jxr_javadoccomment">     * if "foo-1.1.jar" and "foobar-1.1.jar" are in the path, then a logicalLib</em>
<a name="252" href="#252">252</a> <em class="jxr_javadoccomment">     * name of "foo" will match the first entry above.</em>
<a name="253" href="#253">253</a> <em class="jxr_javadoccomment">     */</em>
<a name="254" href="#254">254</a>     <strong class="jxr_keyword">private</strong> URL libFromClasspath(String logicalLib) {
<a name="255" href="#255">255</a>         ClassLoader cl = <strong class="jxr_keyword">this</strong>.getClass().getClassLoader();
<a name="256" href="#256">256</a>         <strong class="jxr_keyword">if</strong> (cl instanceof URLClassLoader == false) {
<a name="257" href="#257">257</a>             <strong class="jxr_keyword">return</strong> <strong class="jxr_keyword">null</strong>;
<a name="258" href="#258">258</a>         }
<a name="259" href="#259">259</a>         
<a name="260" href="#260">260</a>         URLClassLoader ucl = (URLClassLoader) cl;
<a name="261" href="#261">261</a>         URL[] path = ucl.getURLs();
<a name="262" href="#262">262</a>         URL shortestMatch = <strong class="jxr_keyword">null</strong>;
<a name="263" href="#263">263</a>         <strong class="jxr_keyword">int</strong> shortestMatchLen = Integer.MAX_VALUE;
<a name="264" href="#264">264</a>         <strong class="jxr_keyword">for</strong>(<strong class="jxr_keyword">int</strong> i=0; i&lt;path.length; ++i) {
<a name="265" href="#265">265</a>             URL u = path[i];
<a name="266" href="#266">266</a>             
<a name="267" href="#267">267</a>             <em class="jxr_comment">// extract the filename bit on the end of the url</em>
<a name="268" href="#268">268</a>             String filename = u.toString();
<a name="269" href="#269">269</a>             <strong class="jxr_keyword">if</strong> (!filename.endsWith(<span class="jxr_string">".jar"</span>)) {
<a name="270" href="#270">270</a>                 <em class="jxr_comment">// not a jarfile, ignore it</em>
<a name="271" href="#271">271</a>                 <strong class="jxr_keyword">continue</strong>;
<a name="272" href="#272">272</a>             }
<a name="273" href="#273">273</a> 
<a name="274" href="#274">274</a>             <strong class="jxr_keyword">int</strong> lastSlash = filename.lastIndexOf('/');
<a name="275" href="#275">275</a>             <strong class="jxr_keyword">if</strong> (lastSlash &gt;= 0) {
<a name="276" href="#276">276</a>                 filename = filename.substring(lastSlash+1);
<a name="277" href="#277">277</a>             }
<a name="278" href="#278">278</a>             
<a name="279" href="#279">279</a>             <strong class="jxr_keyword">if</strong> (filename.startsWith(logicalLib)) {
<a name="280" href="#280">280</a>                 <em class="jxr_comment">// ok, this is a candidate</em>
<a name="281" href="#281">281</a>                 <strong class="jxr_keyword">if</strong> (filename.length() &lt; shortestMatchLen) {
<a name="282" href="#282">282</a>                     shortestMatch = u;
<a name="283" href="#283">283</a>                     shortestMatchLen = filename.length();
<a name="284" href="#284">284</a>                 }
<a name="285" href="#285">285</a>             }
<a name="286" href="#286">286</a>         }
<a name="287" href="#287">287</a>         
<a name="288" href="#288">288</a>         <strong class="jxr_keyword">return</strong> shortestMatch;
<a name="289" href="#289">289</a>     }
<a name="290" href="#290">290</a> 
<a name="291" href="#291">291</a>     <em class="jxr_javadoccomment">/**</em>
<a name="292" href="#292">292</a> <em class="jxr_javadoccomment">     * Override ClassLoader method.</em>
<a name="293" href="#293">293</a> <em class="jxr_javadoccomment">     * &lt;p&gt;</em>
<a name="294" href="#294">294</a> <em class="jxr_javadoccomment">     * For each explicitly mapped package prefix, if the name matches the </em>
<a name="295" href="#295">295</a> <em class="jxr_javadoccomment">     * prefix associated with that entry then attempt to load the class via </em>
<a name="296" href="#296">296</a> <em class="jxr_javadoccomment">     * that entries' classloader.</em>
<a name="297" href="#297">297</a> <em class="jxr_javadoccomment">     */</em>
<a name="298" href="#298">298</a>     <strong class="jxr_keyword">protected</strong> Class loadClass(String name, <strong class="jxr_keyword">boolean</strong> resolve) 
<a name="299" href="#299">299</a>     <strong class="jxr_keyword">throws</strong> ClassNotFoundException {
<a name="300" href="#300">300</a>         <em class="jxr_comment">// just for performance, check java and javax</em>
<a name="301" href="#301">301</a>         <strong class="jxr_keyword">if</strong> (name.startsWith(<span class="jxr_string">"java."</span>) || name.startsWith(<span class="jxr_string">"javax."</span>)) {
<a name="302" href="#302">302</a>             <strong class="jxr_keyword">return</strong> <strong class="jxr_keyword">super</strong>.loadClass(name, resolve);
<a name="303" href="#303">303</a>         }
<a name="304" href="#304">304</a> 
<a name="305" href="#305">305</a>         <strong class="jxr_keyword">if</strong> (lookasides != <strong class="jxr_keyword">null</strong>) {
<a name="306" href="#306">306</a>             <strong class="jxr_keyword">for</strong>(Iterator i = lookasides.entrySet().iterator(); i.hasNext(); ) {
<a name="307" href="#307">307</a>                 Map.Entry entry = (Map.Entry) i.next();
<a name="308" href="#308">308</a>                 String prefix = (String) entry.getKey();
<a name="309" href="#309">309</a>                 <strong class="jxr_keyword">if</strong> (name.startsWith(prefix) == <strong class="jxr_keyword">true</strong>) {
<a name="310" href="#310">310</a>                     ClassLoader loader = (ClassLoader) entry.getValue();
<a name="311" href="#311">311</a>                     Class clazz = Class.forName(name, resolve, loader);
<a name="312" href="#312">312</a>                     <strong class="jxr_keyword">return</strong> clazz;
<a name="313" href="#313">313</a>                 }
<a name="314" href="#314">314</a>             }
<a name="315" href="#315">315</a>         }
<a name="316" href="#316">316</a>         
<a name="317" href="#317">317</a>         <strong class="jxr_keyword">if</strong> (parentFirst) {
<a name="318" href="#318">318</a>             <strong class="jxr_keyword">return</strong> <strong class="jxr_keyword">super</strong>.loadClass(name, resolve);
<a name="319" href="#319">319</a>         } <strong class="jxr_keyword">else</strong> {
<a name="320" href="#320">320</a>             <em class="jxr_comment">// Implement child-first. </em>
<a name="321" href="#321">321</a>             <em class="jxr_comment">//</em>
<a name="322" href="#322">322</a>             <em class="jxr_comment">// It appears that the findClass method doesn't check whether the</em>
<a name="323" href="#323">323</a>             <em class="jxr_comment">// class has already been loaded. This seems odd to me, but without</em>
<a name="324" href="#324">324</a>             <em class="jxr_comment">// first checking via findLoadedClass we can get java.lang.LinkageError</em>
<a name="325" href="#325">325</a>             <em class="jxr_comment">// with message "duplicate class definition" which isn't good.</em>
<a name="326" href="#326">326</a>             
<a name="327" href="#327">327</a>             <strong class="jxr_keyword">try</strong> {
<a name="328" href="#328">328</a>                 Class clazz = findLoadedClass(name);
<a name="329" href="#329">329</a>                 <strong class="jxr_keyword">if</strong> (clazz == <strong class="jxr_keyword">null</strong>) {
<a name="330" href="#330">330</a>                     clazz = <strong class="jxr_keyword">super</strong>.findClass(name);
<a name="331" href="#331">331</a>                 }
<a name="332" href="#332">332</a>                 <strong class="jxr_keyword">if</strong> (resolve) {
<a name="333" href="#333">333</a>                     resolveClass(clazz);
<a name="334" href="#334">334</a>                 }
<a name="335" href="#335">335</a>                 <strong class="jxr_keyword">return</strong> clazz;
<a name="336" href="#336">336</a>             } <strong class="jxr_keyword">catch</strong>(ClassNotFoundException e) {
<a name="337" href="#337">337</a>                 <strong class="jxr_keyword">return</strong> <strong class="jxr_keyword">super</strong>.loadClass(name, resolve);
<a name="338" href="#338">338</a>             }
<a name="339" href="#339">339</a>         }
<a name="340" href="#340">340</a>     }
<a name="341" href="#341">341</a>     
<a name="342" href="#342">342</a>     <em class="jxr_javadoccomment">/**</em>
<a name="343" href="#343">343</a> <em class="jxr_javadoccomment">     * Same as parent class method except that when parentFirst is false</em>
<a name="344" href="#344">344</a> <em class="jxr_javadoccomment">     * the resource is looked for in the local classpath before the parent</em>
<a name="345" href="#345">345</a> <em class="jxr_javadoccomment">     * loader is consulted.</em>
<a name="346" href="#346">346</a> <em class="jxr_javadoccomment">     */</em>
<a name="347" href="#347">347</a>     <strong class="jxr_keyword">public</strong> URL getResource(String name) {
<a name="348" href="#348">348</a>         <strong class="jxr_keyword">if</strong> (parentFirst) {
<a name="349" href="#349">349</a>             <strong class="jxr_keyword">return</strong> <strong class="jxr_keyword">super</strong>.getResource(name);
<a name="350" href="#350">350</a>         } <strong class="jxr_keyword">else</strong> {
<a name="351" href="#351">351</a>             URL local = <strong class="jxr_keyword">super</strong>.findResource(name);
<a name="352" href="#352">352</a>             <strong class="jxr_keyword">if</strong> (local != <strong class="jxr_keyword">null</strong>) {
<a name="353" href="#353">353</a>                 <strong class="jxr_keyword">return</strong> local;
<a name="354" href="#354">354</a>             }
<a name="355" href="#355">355</a>             <strong class="jxr_keyword">return</strong> <strong class="jxr_keyword">super</strong>.getResource(name);
<a name="356" href="#356">356</a>         }
<a name="357" href="#357">357</a>     }
<a name="358" href="#358">358</a>     
<a name="359" href="#359">359</a>     <em class="jxr_javadoccomment">/**</em>
<a name="360" href="#360">360</a> <em class="jxr_javadoccomment">     * Emulate a proper implementation of getResources which respects the</em>
<a name="361" href="#361">361</a> <em class="jxr_javadoccomment">     * setting for parentFirst.</em>
<a name="362" href="#362">362</a> <em class="jxr_javadoccomment">     * &lt;p&gt;</em>
<a name="363" href="#363">363</a> <em class="jxr_javadoccomment">     * Note that it's not possible to override the inherited getResources, as</em>
<a name="364" href="#364">364</a> <em class="jxr_javadoccomment">     * it's declared final in java1.4 (thought that's been removed for 1.5).</em>
<a name="365" href="#365">365</a> <em class="jxr_javadoccomment">     * The inherited implementation always behaves as if parentFirst=true.</em>
<a name="366" href="#366">366</a> <em class="jxr_javadoccomment">     */</em>
<a name="367" href="#367">367</a>     <strong class="jxr_keyword">public</strong> Enumeration getResourcesInOrder(String name) <strong class="jxr_keyword">throws</strong> IOException {
<a name="368" href="#368">368</a>         <strong class="jxr_keyword">if</strong> (parentFirst) {
<a name="369" href="#369">369</a>             <strong class="jxr_keyword">return</strong> <strong class="jxr_keyword">super</strong>.getResources(name);
<a name="370" href="#370">370</a>         } <strong class="jxr_keyword">else</strong> {
<a name="371" href="#371">371</a>             Enumeration localUrls = <strong class="jxr_keyword">super</strong>.findResources(name);
<a name="372" href="#372">372</a>             
<a name="373" href="#373">373</a>             ClassLoader parent = getParent();
<a name="374" href="#374">374</a>             <strong class="jxr_keyword">if</strong> (parent == <strong class="jxr_keyword">null</strong>) {
<a name="375" href="#375">375</a>                 <em class="jxr_comment">// Alas, there is no method to get matching resources</em>
<a name="376" href="#376">376</a>                 <em class="jxr_comment">// from a null (BOOT) parent classloader. Calling</em>
<a name="377" href="#377">377</a>                 <em class="jxr_comment">// ClassLoader.getSystemClassLoader isn't right. Maybe</em>
<a name="378" href="#378">378</a>                 <em class="jxr_comment">// calling Class.class.getResources(name) would do?</em>
<a name="379" href="#379">379</a>                 <em class="jxr_comment">//</em>
<a name="380" href="#380">380</a>                 <em class="jxr_comment">// However for the purposes of unit tests, we can</em>
<a name="381" href="#381">381</a>                 <em class="jxr_comment">// simply assume that no relevant resources are</em>
<a name="382" href="#382">382</a>                 <em class="jxr_comment">// loadable from the parent; unit tests will never be</em>
<a name="383" href="#383">383</a>                 <em class="jxr_comment">// putting any of their resources in a "boot" classloader</em>
<a name="384" href="#384">384</a>                 <em class="jxr_comment">// path!</em>
<a name="385" href="#385">385</a>                 <strong class="jxr_keyword">return</strong> localUrls;
<a name="386" href="#386">386</a>             }
<a name="387" href="#387">387</a>             Enumeration parentUrls = parent.getResources(name);
<a name="388" href="#388">388</a> 
<a name="389" href="#389">389</a>             ArrayList localItems = toList(localUrls);
<a name="390" href="#390">390</a>             ArrayList parentItems = toList(parentUrls);
<a name="391" href="#391">391</a>             localItems.addAll(parentItems);
<a name="392" href="#392">392</a>             <strong class="jxr_keyword">return</strong> Collections.enumeration(localItems);
<a name="393" href="#393">393</a>         }
<a name="394" href="#394">394</a>     }
<a name="395" href="#395">395</a>     
<a name="396" href="#396">396</a>     <em class="jxr_javadoccomment">/**</em>
<a name="397" href="#397">397</a> <em class="jxr_javadoccomment">     * </em>
<a name="398" href="#398">398</a> <em class="jxr_javadoccomment">     * Clean implementation of list function of </em>
<a name="399" href="#399">399</a> <em class="jxr_javadoccomment">     * {@link java.utils.Collection} added in JDK 1.4 </em>
<a name="400" href="#400">400</a> <em class="jxr_javadoccomment">     * @param en &lt;code&gt;Enumeration&lt;/code&gt;, possibly null</em>
<a name="401" href="#401">401</a> <em class="jxr_javadoccomment">     * @return &lt;code&gt;ArrayList&lt;/code&gt; containing the enumerated</em>
<a name="402" href="#402">402</a> <em class="jxr_javadoccomment">     * elements in the enumerated order, not null</em>
<a name="403" href="#403">403</a> <em class="jxr_javadoccomment">     */</em>
<a name="404" href="#404">404</a>     <strong class="jxr_keyword">private</strong> ArrayList toList(Enumeration en) {
<a name="405" href="#405">405</a>         ArrayList results = <strong class="jxr_keyword">new</strong> ArrayList();
<a name="406" href="#406">406</a>         <strong class="jxr_keyword">if</strong> (en != <strong class="jxr_keyword">null</strong>) {
<a name="407" href="#407">407</a>             <strong class="jxr_keyword">while</strong> (en.hasMoreElements()){
<a name="408" href="#408">408</a>                 Object element = en.nextElement();
<a name="409" href="#409">409</a>                 results.add(element);
<a name="410" href="#410">410</a>             }
<a name="411" href="#411">411</a>         }
<a name="412" href="#412">412</a>         <strong class="jxr_keyword">return</strong> results;
<a name="413" href="#413">413</a>     }
<a name="414" href="#414">414</a>     
<a name="415" href="#415">415</a>     <em class="jxr_javadoccomment">/**</em>
<a name="416" href="#416">416</a> <em class="jxr_javadoccomment">     * Same as parent class method except that when parentFirst is false</em>
<a name="417" href="#417">417</a> <em class="jxr_javadoccomment">     * the resource is looked for in the local classpath before the parent</em>
<a name="418" href="#418">418</a> <em class="jxr_javadoccomment">     * loader is consulted.</em>
<a name="419" href="#419">419</a> <em class="jxr_javadoccomment">     */</em>
<a name="420" href="#420">420</a>     <strong class="jxr_keyword">public</strong> InputStream getResourceAsStream(String name) {
<a name="421" href="#421">421</a>         <strong class="jxr_keyword">if</strong> (parentFirst) {
<a name="422" href="#422">422</a>             <strong class="jxr_keyword">return</strong> <strong class="jxr_keyword">super</strong>.getResourceAsStream(name);
<a name="423" href="#423">423</a>         } <strong class="jxr_keyword">else</strong> {
<a name="424" href="#424">424</a>             URL local = <strong class="jxr_keyword">super</strong>.findResource(name);
<a name="425" href="#425">425</a>             <strong class="jxr_keyword">if</strong> (local != <strong class="jxr_keyword">null</strong>) {
<a name="426" href="#426">426</a>                 <strong class="jxr_keyword">try</strong> {
<a name="427" href="#427">427</a>                     <strong class="jxr_keyword">return</strong> local.openStream();
<a name="428" href="#428">428</a>                 } <strong class="jxr_keyword">catch</strong>(IOException e) {
<a name="429" href="#429">429</a>                     <em class="jxr_comment">// TODO: check if this is right or whether we should</em>
<a name="430" href="#430">430</a>                     <em class="jxr_comment">// fall back to trying parent. The javadoc doesn't say...</em>
<a name="431" href="#431">431</a>                     <strong class="jxr_keyword">return</strong> <strong class="jxr_keyword">null</strong>;
<a name="432" href="#432">432</a>                 }
<a name="433" href="#433">433</a>             }
<a name="434" href="#434">434</a>             <strong class="jxr_keyword">return</strong> <strong class="jxr_keyword">super</strong>.getResourceAsStream(name);
<a name="435" href="#435">435</a>         }
<a name="436" href="#436">436</a>     }
<a name="437" href="#437">437</a> }
</pre>
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